Electron-discharge tube



ELECTRON DI SCHARGE TUBE Filed June 28, 1923 INVENTOR. 1 i? 3 I SM Y W K MQ ATTORNEYS.

Patented Feb. 3, 1925.

. UNITED STATES SAMUEL RUBEN, OF NEW YORK, N. Y.

ELECTRON-DISCHARGE TUBE.

Application filed June 28, 1828. Serial No. 648,898.

To all whom it may concern:

Be it known that I, SAMUEL RUBEN, a citizen of the United States, and resident of New York city, in the county of New York and State of New York, have invented certain new and useful Electron-Discharge Tubes, of which the following is a specification.

This invention relates to an electron discharge tube; and more particularly, it re.- lates to an electron discharge device for the detection and amplification of radio frequency oscillations. Its object is to provide an efficient low cost means for detecting and amplifying received radio frequency oscillations.

In the prior art there are two types of electron discharge tubes, the two element tube employing a hot cathode and a cold anode and functioning by virtue of the rectification efiected by means of the hot cathode; and the three element tube, employing the hot cathode and an anode, and

a third element for electrostatically modulating the electron discharge from the oathode to the anode. The tube of my invention is of the former type, but possesses the characteristics of the latter.

Broadly, my invention consists of a vacuum tube apparatus, the electron discharge of which traverses an electrostatic field between the cathode element and the anode, and having an insulating plate element inter osed across the normal direct path of that ischarge to the anode, which is forced thereby to travel across the electrostatic field in a direction approaching an angle of 4.5 degrees to the direction of the field, by the variations in which, in response to radio frequency oscillations impressed u on the anode-cathode circuit, the electron dlscharge is modulated.

As arranged, the cathode and anode, comprising conductive surfaces in combination, act as condenser electrodes, between which, when radio frequency oscillations are impressed, a capacity current flows transverse of the electron current. Thus, this two ele- -ment tube rectifies im ressed oscillations illustrative embodiment of the invention whichtube;

Fig. 2 is a sectional view of the contained elements, and indicates the directions of the electron stream and the capacity current;

Fig. 3 is a diagram of a radio receiving circult in which the tube is connected.

Referring more particularly to Fig. 1, 1 is a receptacle composed of-glass or other suitable material, containing a filament cathode 6, and an anode 2, the former supported by and in conductive relation with plates 3 and 4, of lar e area for lar e electrostatic capacity. pposite the h ament cathode 6, and attached to anode 2, is a mica plate 5, t0 deflect the electron stream from its normal direct path to the anode 2, forcing it to traverse the electrostatic field in a direction approximately degrees to that of the field in the space between plates 3 and 4, and anode 2,-the lead from which latter is at 9, and those from the cathode at 7 and 8.

For some uses the mica surface adjacent the cathode, can with advantage be coated with a conductive material, such, for instance, as graphite. I

By extending the anode element to the opposite side of the plane of the filament and its supporting plates, and interposing a non-conductive material, as in the first instance, a more eficient use of the electron discharge from the filament is efiected.

In Fig. 3, L indicates the generally used tuning inductances, the secondary connected to anode element 2, and'to battery B which furnishes the potential for the electron discharge between the electrodes. A. telephone receiver T, translates the. impressed electrical oscillations into sound waves. 0, is a by-pass condenser for radio fre uency oscillations, and B is a battery for eating the cathode toemission temperature, controlled by resistance R. I

In operation, when the cathode is 'sufiiciently heated by battery B for electron emission, a current flows between the oathode andanode and through the circuit including telephone receiver T. Radio frequency oscillations impressed upon the anode-cathode circuit from the secondary of the tuning device L, cause the discharge Fig. 1 is a vertical sectional view of the of a capacity current between cathode plates sponse to the impressed oscillations, modulates the electron discharge traversing it. It has been found that, forthe most efficient modulation of that discharge, the angular relation between the discharges is about 45 degrees.

Modulations of the electron discharge are translated by telephone receiver T.

If used fore detection purposes only, this apparatus need not be so highly evacuated as for purposes of amplification.

1. An electron discharge tube com rising an evacuated vessel having therewi't in an electron emission element, a cooperating plate or anode element and an element composed of an'insulatin -material, interposed therebetween, and e ectrically conductive plates arranged ina plane approximately parallelto said anode element, said emission element being in conductive relation with said conductive plates.

2. An electron discharge tube comprising an evacuated vessel having therewithin an electron emission element, a cooperating plate or ane element and an element comparallel to said anode element, said emission element being in conductive relation with said conductive plates.

3. An electron discharge tube comprising an evacuated vessel having therewithin an electron emisslon element, a cooperating plate or anode element, and electrically con ductive plates arranged in a plane approximately parallel to said anode element, said emission element being in conductive relation with said conductive plates and means i for deflecting the electron discharge from.

its normal path to said anode element to a path transverse of the direction of a capac- -1ty current flowing between said conductive plates and said anode Signed at New York city, in the county of New .York and Statepf New York, this 23rd day of June, A. Dr 1923.

v SAMUEL RUBEN. 

